19 April 1996

Flowering rape linked to breathing problems

NATURAL chemicals released by flowering oilseed rape plants pose problems to human health, according to research results released by the Scottish Crop Research Institute.

Trials conducted over the last four years suggest that the volatile organic compounds given off by flowering OSR can cause hay-fever, asthma and breathing difficulties.

The findings overturn previous research in Aberdeen, reported recently in a House of Commons written reply, which suggested there was no firm evidence of any link between OSR and hay-fever.

Dr Bill Macfarlane-Smith, SCRI head of scientific liaison and project leader, said three-year tests recording the health of 22 residents of the Tayside village of Stormontfield, near Perth, had found evidence of the effects of OSR.

"In the first year of the study, the village was surrounded by OSR, and we monitored the daily health before, during and after flowering, the chemical applications to the crop and the volatile release of organic compounds.

"There was no evidence that the applied chemicals caused any problems, but during flowering people experienced runny noses, coughs, sneezes and in exceptional cases breathing problems.

"During the following two years, the nearest OSR crop was two kilometres away, but all other natural phenomena remained the same. There was a marked difference in health between the first and other two years."

Further research last year looked at whether the pollen or other fungal spores released by the crop were the cause, and analysed natural chemical compounds.

Dr Macfarlane-Smith said a pilot test last spring/summer involving 10 asthmatics also found their symptoms closely matched the flowering of winter and spring sown OSR.

"We want to try and confirm those tests using 40 asthmatics this year, looking especially at the lung function."

Tony McDougal